Impact of Surface Laser Treatment on Magnetostriction and Magnetoelastic Properties of the GO FeSi Electrical Single Sheet
Résumé
Grain-oriented elctrical steel is generally used in electrical machines like transformers. Laser surface treatment of such materials mainly used for iron losses reduction may also reduce noise and vibration due to magnetostrictive loads reduction. Surface laser treatment supplies additional stresses that changes the domain structure's configuration and modifies the magnetic and mechanical behavior. Laser treatment effect on magnetoelastic properties that characterize the magnetostrictive behavior is proposed. Experimentations are established in a single sheet tester (SST) where mechanical and magnetic macroscopic transient signals, as such the acceleration, the average induction and the applied magnetic field are synchronously measured. Mesoscopic magnetostrictive strain is identified with the measurements using a simple finite element mechanical approach. Next, magnetomechanical coupling between the magnetization process sensitive to laser treatment and the induced magnetostriction is considered for characterizing magnetoelastic properties. The latter are correlated with the static and dynamic mesocopic properties derived from the identification of the measured magnetic signals and the 1-D Maxwell diffusion model. We finally propose a parametric study that helps to understand the effect of different laser treatments on the magnetostrictive strain and the identified magnetoelastic properties. This strategy is the key for the reduction and eventually the optimization of noise and vibration in electrical machines next to iron losses reduction.